[Bug 15492] New: Clamwin installer doesn't parse %SystemDrive% correctly

http://bugs.winehq.org/show_bug.cgi?id=15492

Summary: Clamwin installer doesn't parse %SystemDrive% correctly
           Product: Wine
           Version: 1.1.5
          Platform: Other
               URL: http://sourceforge.net/project/downloading.php?groupname
                    =clamwin&filename=clamwin-0.94-
                    setup.exe&use_mirror=superb-east
        OS/Version: other
            Status: NEW
          Keywords: download, Installer, source
          Severity: minor
          Priority: P2
         Component: -unknown
        AssignedTo: [e-mail]
        ReportedBy: [e-mail]

Created an attachment (id=16404)
 --> (http://bugs.winehq.org/attachment.cgi?id=16404)
+shell in git, bzip2 -9'ed

Installing Clamwin works fine, except that instead of installing to:
C:\Program Files\Clamwin

it defaults to:
Z:\home\austin%SystemDrive%\Program Files\ClamWin

I've seen this on a couple other installers as well, but can't think of them
off hand.

+shell attached